My wife and I like going on cruises, and I've taken pictures inside the last cruise liner we went on to show what it was like. Why post about it? Holiday snaps are a dime a dozen, and the insides of a cruise liner are not as memorable as the Pyramids or Great Wall of China.
These pictures have been arranged as a kind of game. The game can be played without any puzzles, the puzzles available require a certain kind of mathematical thinking.